His mother Nicola Urquhart told ITV's Good Morning Britain programme, "Yes, I do" when asked if she believes the gunner is still alive.

The 48-year-old said: "There are only three possibilities, he has been in a dreadful accident, perhaps and this is one I think is most likely, he would go with a stranger in their car, he would ask a stranger for a lift."

Ms Urquhart added: "Perhaps someone has given him a lift and taken to him to the wrong place and they feel bad and they don't to come forward but the police don't know where to search."

She said the police have searched the route to RAF Honington where he was based from his last known location and found nothing and asked anyone who may have helped him to contact the police.

Officers have searched a railway line, A-roads and hours of CCTV has been reviewed in the search for the member of RAF Regiment 2 Squadron.

In the early stages of the investigation a bin lorry was searched, after Corrie's phone was believed to have been lost or discarded and ended up in the rubbish, but it has yet to be recovered.

Earlier Suffolk police revealed they were searching for three teenagers in connection with the disappearance of Corrie, they have since been traced.

Ms Urquhart added: "He could have had an accident by whatever means and it would mean he would now unfortunately mean he is dead or he is has left voluntarily but there has been now preparation, no motivating factor to make him go."

She said her son's life "was going really well just now".

The other option mentioned was that of abduction.

She said: "I don't think that is got anything to do with terrorism, I'm aware of the Marham incident however there is only one but of evidence against that, that is because nobody has claimed him."

According to Ms Urquhart the police are not ruling anything out but the abduction line is not actively being investigated.

A spokesman for Suffolk Constabulary said: "We haven't had any evidence at all of any third party involvement. We have got to keen an open mind."

Anyone who may have been out in Bury St Edmunds between 3am and 6am on Saturday 24 September or anyone with information that may assist is urged to please call the incident room on 01473 782019.